interviewing with a different guy

today i had an interview. before i was told that the manager would interview me. so when i got the call i said good morning mr. x because i was supposed to talk to him. the guy over the phone didn t say i m not mr. x and we continued. during the interview i was thinking i was talking to the manager.but on the other hand i felt like the guy sounds so young for a manager and he doesn t have manner like a manager. after the interview i wanted to send a thank you later and also i wanted to figure out who was the interviewer and i called human resources department and i said i had an interview today and the guy over the phone didn t correct me that i wasn t talking to the manager but i have doubts that he is the manager they told me no he was the manager. but i wasn t satisfied. then i found the real manager's extension and i said mr. x we were supposed to have an interview today and i talked with a gentleman and i called him with your name and he didnt correct me but i felt it wasn t you he said sorry because he had an urgent issue on behalf of him another person interviewed me i asked his email address to send him a thank you letter and thanked him.

did i act weirdly by chasing after who interviewed me? and why didn't the guy over the phone tell me he isn t the manager? i felt disappointed. but at the end while i was talking to the real manager he sounded very friendly and he told me he wish to meet me in person interview.